【作者】 武剑辉；

【导师】 向敬成； 陈辅新；

【作者基本信息】 电子科技大学 ， 信号与信息处理， 2001， 博士

【摘要】 现代雷达系统广泛采用脉冲压缩技术，在确保雷达作用距离和速度分辨力的前提下，采用大时宽带宽积脉冲压缩信号：如线性调频（LFM）、非线性调频（NLFM）信号以及相位编码信号等，提高距离维分辨能力。脉冲压缩技术包括脉压信号的产生和处理两个关键的技术。随着科学技术的进步，脉压处理系统从模拟式、数模结合式发展到全数字式，而数字脉压处理又可分为时域脉压处理和频域脉压处理。 本文主要研究了在数字脉压处理技术中占有显著优势的频域数字脉压处理技术，分析了多种脉压信号的频域脉压性能及其距离旁瓣抑制滤波器的设计方法，并在此基础上研制成功了多波形频域数字脉冲压缩处理系统。该系统可处理压缩比256以内、带宽5MHz以下的线性调频、非线性调频波形及相位编码信号，技术指标完全满足实用系统的设计要求，并取得了比较满意的结果。 本文完成的主要工作和创新之处有： （1）对压缩比在95～250范围内的多种脉压信号频域压缩处理性能进 行了比较全面的分析研究。 （2）分析了数字处理中采样率对系统关键指标主副比的影响，并基于 实际系统常使用的Nyquist速率采样情况下进行设计处理，得出 了对实际应用十分重要的研究结论。 （3）采用多种频域窗函数综合出了一组大时带积NLFM脉冲压缩信 号，其中部分窗的应用尚未见类似的研究报道，本文模拟分析了 这类信号的分辨力和多普勒响应性能，并与实验结果进行分析比 较，总结了设计大时带积非线性调频脉压信号窗函数的选择原 则。该组信号应用于远程警戒雷达可收到增大检测目标动态范围 而不降低作用距离的实效。 （4）对二相编码信号旁瓣抑制滤波器（SSF）的研究已有很长时间，但 对长码信号的频域处理研究尚未见报道。本文从二相编码信号的 频谱结构分析入手，采用频域数字处理方法，研究了二相编码长 码雷达信号距离旁瓣频域抑制加权技术。提出一种适用于各种码 长信号的SSF频域设计方法。 0—— o）J W Tylor提出了一类性能优良的四相码，并对 13上8位 Tyor 四相码信号进行了性能研究。本文对较长的 Tylor四相码信号进 行比较全面的分析，并首次采用频域数字处理方法，研究了四相 编码长码雷达信号距离旁瓣频域抑制滤波技术。 N）分别以 12 7位二相编码和 Tylor四相码为例，对 SSF处理性能 进行仿真分析和实验测试。当fd刃时，仿真与实测结果的主副 比分别超过了50dB和43dB。这表明采用这种方法所设计的相位 编码信号SSF可以应用于现代雷达系统，并得到满意的性能指 标。 （）采用高速 FFT快速付里叶变换）专用芯片研制成功一套适用于多 种波形和多种参数脉压信号的频域数字脉冲压缩处理系统，信号 处理输出的主副比超过30dB，满足了实际雷达应用的要求。更多还原

【Abstract】 Pulse compression technique is widely used in modem radar systems. Large timeband product signals such as linear frequency modulation signals (LFM), nolinear frequency modulation signals (NLFM), phase coded signals and so on are used in pulse compression technique to improve the resolution in range domain. Pulse compression technique includes two key techniques: the pulse compression signal generation and processing. With the progress of science and technology, pulse compression processing systems are developed to all-digital systems from analogue or digital-analogue ones. Digital pulse compression processing can be divided into pulse compression processing in time domain and pulse compression processing in frequency domain. This dissertation mainly studies the digital pulse compression processing technique in frequency domain, which possesses the remarkable advantages in digital pulse compression processing. Pulse compression performances of many pulse compression signals are analyzed in frequency domain. And the methods to design kinds of range sidelobe suppression filters (5SF) are proposed. Based on the theoretic analysis and computer simulations, a multi- waveform pulse compression system in frequency domain is successfUlly exploited, which is applicable to complete pulse compression processing of linear frequency modulation, nonlinear frequency modulation waveforms and phase coded signals. The designed bandwidth of signals reaches 5MHz and pulse compression ratios are under 256. The experimental results demonstrate that the specification characteristics meet the requirements of practical radar systems. And the results are satisfactory. The main content and creative work in this dissertation include: (1) The characteristics of various pulse compression signals with 95 -?~25O pulse compression ratios is comprehensively investigated in frequency domain. (2) The effect of the sampling rate on RMS, the crucial performance of the pulse compression, is analyzed. The signal design and processing are based on the practical Nyquist sampling frequency and the results of the computer simulations conform to that of the system experiments. (3) A group of large time-bandwidth product NLFM signals are synthesized with various window-functions in frequency domain and the analogous application of some window- functions have not been reported before. Meanwhile, the computer simulation results of the signal resolution and Doppler response are also discussed and compared with the actual experimental results. At last, the selection principles of window function for large time- ?-. bandwidth product NLFM signals are proposed. These signals can be used in long-range radars and will increase the dynamic range of target detection. (4) The sidelobe suppression filters (SSF) for biphase coded signals have been researched for long time. But the research on long-code signal processing in frequency domain has not been reported before. This dissertation studies the range SSF techniques for long-biphase coded signals by applying digital processing in fi~quency domain. By analyzing the spectrum characteristics, a SSF design method in frequency domain which is suited for various code lengths is presented. (5) J. W Taylor and etc. have presented a class of quadriphase coded signal with good properties, and described the characteristic of 13-28-bits signals. The dissertation gives the details of longer quadriphase coded sig更多还原